Fuel preheaters for internal combustion engines are known in the prior art and are generally for the purpose of improving engine starting and efficiency of operation with a reduction of air pollutants.
Some prior art devices for this purpose are electrically operated and examples of electrical devices are disclosed in U.S. Pat. Nos. 4,342,303 and 4,391,259. In the latter patent, an axially short electrical heating element is exposed inside of a fuel heating chamber placed in the fuel line leading to the carburetor.
Other known fuel preheating devices are non-electrical and derive heat from the internal combustion engine cooling system. An example of this is shown in U.S. Pat. No. 4,395,997.
The known prior art devices have tended to be too complex and costly in their constructions to be fully practical. Moreover, they have failed to increase the operational efficiency of the engine to a degree necessary to justify the installation and use of the device.
Accordingly, it is the object of the present invention to provide a fuel preheating unit of the above-mentioned type which is simpler and less costly to manufacture and install than known prior art devices and which provides significantly greater advantages than any of the known devices for the same general purpose. More particularly, the fuel preheater according to the present invention causes more complete and efficient burning of gasoline, therefore resulting in significantly better mileage in automotive usage. It lessens the cost of engine maintenance by reducing engine wear, due to the elimination of wet gasoline which may pass around the piston rings. These and other known advantages stated in the prior art patents are present in this invention.
A further object of the invention is to provide a fuel preheating unit of extremely simplified construction which is easy to install and requires virtually no attention or maintenance after installation.
Other features and advantages of the invention will become apparent to those skilled in the art during the course of the following description.